ABSTRACT
The article estimates the exposure of the population of Qatar to aflatoxins, fumonisins and ochratoxins, measured in food samples collected from the markets of Doha. The mycotoxin extractions were performed using the "Quick Easy Cheap Effective Rugged Safe" Method (QuEChERS) and the extract measured with LC-MS/MS. High contamination with aflatoxins was detected in Nuts and Spices (e.g. 534.15 ng/g and 371.6 ng/g respectively). The estimated daily intake (EDI) level was estimated using statistical data on average Qatari population. Additionally, the probability to exceed TDI was calculated for fumonisins and ochratoxins. The results indicate high exposure to aflatoxins (with alarming values of margin of exposure, i.e. MoE). The article points to the necessity of a regular assessment and reevaluation of the concentration limits allowed in food products accounting for statistics on the population (i.e. food consumption), economic growth of the country, and monitoring of mycotoxin contamination of food as much as technological, financial and human resources of a country allows.
ABSTRACT
Most countries have clearly defined regulations governing the use of pesticides in agricultural activity. The application of pesticides in agriculture usually leads to a residual amount of these pesticides on food products such as fruit and vegetables. The presence of pesticide residues on these foods destined for human consumption may pose food safety risks to consumers. To protect consumers, national authorities have established maximum limits for pesticide residues in foods. These limits can only be enforced if there are methods available to detect and monitor their concentrations in the applicable food products. To support the enforcement of this legislation, we have developed a multi-residue liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for the analysis of 120 pesticide residues in apples and cucumbers which has been validated and implemented in the routine monitoring and surveillance programme for these pesticides. In this method, apple and cucumber samples are extracted using the QuEChERS method (quick, easy, cheap, effective, rugged, and safe) and the extracts were analyzed directly by LC-MS/MS. The mean recoveries at three different concentrations of 0.01 µg/g , 0.05 µg/g, and 0.1 µg/g over the analytical range varied between 70 and 120%. The repeatability of the method expressed as %RSD was less than 20%. The limit of detection (LOD) of the method ranged between 0.0014 and 0.0110 µg/g for apples and between 0.0012 and 0.0075 µg/g for cucumbers. The limit of quantification (LOQ) of the method was 0.01 µg/g for apples and cucumbers. The method has been used for the analysis of over 600 apple and 550 cucumber samples over the past two years. Copyright © 2016 John Wiley & Sons, Ltd.
